> I thought you were suggesting that we don't do the get_last_attnums (and> inlined version in the isSimpleVar case) at execution time anymore,> instead relying on logic in the planner to know how much to deform ahead> of time. Then we'd do slot_getsomeattrs in the appropriate places. But> I understood you suggesting to do so only in scan nodes - which doesn't> seem sufficient, due to the use of materialized / minimal tuples in> other types of nodes. Did I misunderstand?

We would need to do it anywhere that we might be projecting from amaterialized tuple, I suppose. From the planner's standpoint it would beabout as easy to do this for all plan nodes as only selected ones.

Anyway the core point here seems to be that skipping ExecProject misses abet because the underlying tuple doesn't get disassembled. A quick-hackway of seeing if this helps might be to do slot_getallattrs in the placeswhere we skip ExecProject. I'm not sure we'd want that as a permanentsolution, because it's possible that it extracts columns not actuallyneeded, but it should at least move the hotspot in your example case.